In the fields of orthodontics and maxillofacial surgery, a dental articulator apparatus includes visible coding on articulator components to indicate the present positions of a person's teeth and jaws with respect to goals of orthodontic and/or surgical treatment. From another aspect, the visible coding indicates at least a direction, and preferably, a direction and a distance, which a person's teeth and/or jaws must be moved by orthodontics treatment and/or by surgery to achieve the goals.
Orthodontic practice has undergone a significant evolution in the past fifty years, with new diagnostic and treatment techniques emerging and rapidly replacing the standard practices of the preceding century. In the 1950s and 1960s, research was undertaken to determine optimal occlusion, in terms of quantifying dental arch characteristics and tooth positions of naturally optimal dentitions. See Andrews, L F. The Six Keys To Normal Occlusion. Am. J. Orthod. 1972; 62:296-309. See also Andrews L F. Straight Wire, The Concept and Appliance. San Diego: LA Wells Co; 1989; 407 p. Since 1970, this information has been practiced by orthodontists worldwide. From 1970 to 1990, research was undertaken to learn if individuals with balanced faces shared arch and jaw position characteristics. Such characteristics were found and reported. See Andrews L F, Andrews W A. Syllabus of the Andrews Orthodontic Philosophy, 9th edition, 2001, and Andrews L F, ed. Six Elements Orthodontics. The Andrews Journal of Orthodontics and Orofacial Harmony. 2000; 1: 8-33. This information has led to a method of orthodontic analysis and treatment called the Six Elements of Orofacial Harmony™.
According, to the Six Elements method, analysis of the relationship between the teeth, the jaws, and the face of a person is conducted using a set of goals (the Six Elements). The quality of the positions of the teeth or jaws relative to an Element is measured relative to anatomical landmarks. In this regard, an anatomical landmark is an anatomical point or line having a uniquely correct aesthetic and positional relationship with the teeth or jaws when they are optimally positioned. For example, optimal arch shape (Element I), is measured relative to the Wala ridge. And, optimal tooth positions are measured relative to the occlusal plane. For optimal orofacial harmony, the teeth and jaws are measured with respect to anatomical landmarks that relate optimal occlusion to facial balance. By way of illustration, one such landmark, used to determine anteroposterior (AP) jaw position, is the Goal Anterior Limit Line (GALL). The GALL is defined with respect to a Facial Axis Point (FA Pt) on the forehead and is located on the face, at or anterior to, the FA Pt in respect to the inclination of the forehead. The optimal locations of the upper and lower jaws are defined relative to the GALL. AP jaw positions are considered to be optimal when both arches are optimal. (Element I), interarch relationship is optimal (Key I of the Six Keys), and the FA Pt of the maxillary central incisor touches the GALL. See Schlosser J B, Preston C B, Lampasso J. The effects of computer-aided anteroposterior maxillary incisor movement on ratings of facial attractiveness. Am. J. Orthod. & Dentofacial Orthop. 2005 January; 127(1):17-24. See also, The Andrews Journal of Orthodontics and Orofacial Harmony. 2000; 1: 8-33.
Orthodontic practice has historically utilized a number of useful tools to assess dental condition, to aid in diagnosis and treatment planning, and to counsel patients. For example, models of a person's teeth and jaws are taken in the form of maxillary (upper jaw) and mandibular (lower jaw) casts. The casts are mounted on a machine called an articulator, which represents the bony skeleton of the jaws and jaw joints. See U.S. Pat. No. 5,176,515. See also the Occlusofacial Simulator System available from Golden Eagle Orthodontics, Inc. and described at the website accessed through www(dot)geo-orthodontics(dot)com. Casts are located on the articulator in the same orientation to the jaw joints, planes of the head, and each other as the teeth and jaws are on the person. Thus, when mounted on an articulator, the casts provide an orthodontist and/or a maxillofacial surgeon with a model that simulates the person's oral condition. That information, along with photographs, x-rays, and charts, allows the person's orofacial condition to be measured and helps the practitioner to determine a course of treatment designed to position the person's teeth and/or jaws with respect to goals of the treatment. When treatment is completed, final records can be taken to record and assess the quality of the treatment.
Designs of orthodontic diagnostic tools have changed to accommodate the needs of the new diagnostic techniques. For example, some articulators have been adapted to illustrate a person's pretreatment condition with respect to certain landmarks that help define a desired post-treatment condition. Relatedly, the Occlusofacial Simulator Articulator System available from Golden Eagle Orthodontics employs a simulated temporomandibular joint (TMJ), the posterior border of the oral complex, and a GALL rod mounted to a maxillary cast support member to show the proposed anterior border. However, other than for the posterior border, traditional articulators do not indicate where the pretreatment positions of teeth, arches, and jaws are with respect to intended positions, or where those pretreatment positions should be moved, in order to achieve specific post-treatment goals. Instead, such information is provided on patient charts, where the present positions of a person's teeth and jaws with respect to post-treatment goals are recorded in long hand or by means of coded markings.
As an example, the principal mode of recording a person's condition for diagnosis and treatment according to the Six Elements of Orofacial Harmony Philosophy uses intended goals or optimal outcomes. The present positions of the person's teeth and jaws are measured relative to optimal goals, which are the Six Elements of Orofacial Harmony or as close to them as circumstances permit. These measurements are recorded in the dental chart. The system of recordation may use colors, or words or letters that indicate colors, to signify the direction, and numbers to indicate the distance. Green (G) indicates that a measured position of a tooth, arch, or jaw is optimal with respect to a particular goal, which implies that no movement of teeth, arch, or jaw is necessary. Red (R) indicates that the position is anterior, superior, or buccal, relative to optimal, which implies that compensatory posterior, inferior, or lingual movement is necessary to achieve the goal. Black (B) indicates that the position is posterior, inferior, or lingual relative to optimal, which implies that compensatory anterior, superior, or buccal movement is necessary to achieve the goal. In each instance, if the amount of movement is interesting, it is entered in millimeters. See Andrews L F, ed. Six Elements Orthodontics. The Andrews Journal of Orthodontics and Orofacial Harmony. 2000; 1: pp. 24-25.
Presently, a practitioner cannot begin to plan, or visualize a manifold treatment strategy including movement of teeth and/or jaws simply by viewing an articulator with casts mounted thereto. Instead, other sources of information must be consulted while the articulator-mounted casts are studied. Separately, the diagnostic effort, and the attendant patient counseling, is encumbered with casts, charts, records, x-rays, and other paraphernalia necessary to convey relevant information about a person's dental condition and the intended goals of treatment.
Accordingly, extremely positive and useful results in record-keeping, diagnosis, treatment, and counseling would be realized by consolidating the information about a person's dental condition and simplifying the presentation of such information in the tools used by orthodontists and maxillofacial surgeons. These results are realized by adaptation of an articulator apparatus to visibly denote the present positions of a person's teeth and jaws with respect to intended post-treatment goals. Stated another way, there is a need for an articulator-mounted dental model that visually integrates both the pretreatment condition of a person's teeth and jaws as well as the intended goals to be achieved by treatment of the condition.